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The brain and neural structures in the human body are generally unforgiving. From cerebral palsy to strokes, from spinal cord injuries to football-related head trauma, “making better” rather than “correcting” tends to be the medical dictum. Hearing loss is a spectacular instance where something can, in fact, be done.
In 1984, the first single-channel cochlear implant for adults, allowing sound detection and some awareness of voice, although not “hearing” as we know it, was approved by the FDA. This was followed, in 1990, at about the same time as the new recommendations for universal newborn screening, by a new multichannel cochlear implant with complex speech processing ability, approved for young children. For the first time in history, a child born deaf would be able to hear at an age when the brain pathways for language were being created.
It's important to understand why the timing of these two coinciding events was so critical. By the end of age three, the human brain, including its one hundred billion neurons, has completed about 85 percent of its physical growth, a significant part of the foundation for all thinking and learning. The development of that brain, science shows us, is absolutely related to the language environment of the young child. This does not mean that the brain stops developing after three years, but it does emphasize those years as critical. In fact, the diagnosis of hearing loss in babies had often been called a “neurologic emergency,” essentially because of the expected negative impact on a newborn's development.
The importance of early screening coinciding with cochlear implantation for children cannot be overstated. If they had not taken place simultaneously, if, for example, diagnoses of deafness came at a later age, and the cochlear implant had been placed in older children's ears, the cochlear implant may have been deemed a fabulous piece of technology but not much more, certainly not the game changer that it is. That's because successful cochlear implantation requires neuroplasticity, the ability for a brain to develop with new stimuli. And although neuroplasticity for learning language may occur, to some degree, at all ages, it is integral to the young brain from birth through about three to four years of age. Exceptions are those who have gone deaf after having learned to talk and whose brain's language pathways are already established. Those who are born deaf and receive implantation at a much later age will hear sounds, but rarely will they gain the ability to understand their meanings.
I soon learned, however, that even when cochlear implants are put in place at an optimum time, there are other factors that may preclude their success.
The University of Chicago is an island in a sea of inequality on Chicago's South Side. Adding to the overwhelming social and economic challenges facing many families on Chicago's South Side, before I began my cochlear implant program there was the added barrier of communication between children born deaf and their families. This presented both a remarkable opportunity and an extraordinary challenge for me and my incredible, dedicated cochlear implant team. It would also prove to be the experience that would entirely change the direction of my thinking and my career.
When I was an infant in the late 1960s, at the height of the civil rights conflict, my mother, a social worker, took me to work with her in inner-city Baltimore. I slept in a room near her office with someone sitting outside of the door to tell her when I woke up. Later that year, sent to Peru to do a study of the possibilities for creating infant care centers in the barriadas circling Lima, she would sometimes carry me through the hills on her back in an aluminum-sided baby carrier, an “in,” she said, with skeptical inhabitants who had never seen a foreigner do that. Much later she told me that whatever she did, anywhere, never came close to how much she learned, especially about the wealth of untapped potential in people who never had a chance. It's the same experience I've had with my own patient population. Little did I know, when I began this journey, that one of the biggest impacts of my work would be, in fact, on me.
My cochlear implant program at the University of Chicago started slowly. Patients weren't, as I had thought they would be, lining up at my door like at a big sale day at a shopping mall. But it was the slow start that gave me a crucial perspective I might otherwise have overlooked.
Because there were so few, I tended to each patient as if he or she were my own child, noticing each milestone, a first smile, a first step, with all the pride of a parent. I was present at every activation, the moment a child's cochlear implant is turned on and sound is heard for the first time. And, like a parent, while I was rejoicing successes, I was also agonizing when things were not as they should have been.
The problems I saw bothered me tremendously; lagging responses to first hearing sound, lack of reaction to hearing their names, slowness in saying a first word or reading a first book. Adding to this burden was the fact that the profound differences I saw occurred in children who had looked very similar to the others at the outset. The path to find out why would eventually lead me into the world of children born hearing.
The truth is, at one time I would have likely dismissed my observations of the children as non-science, interesting anecdotes at best. For me, as for many others in academia, science became “true” science only when the numbers were big enough to prove or disprove something, a sample size with “power,” as we say. But I soon came to realize that the power of numbers, disregarding the significance of individual experience, can obscure important insights.
Zach was my second cochlear implant patient; Michelle, my fourth. Both diagnosed as profoundly deaf at birth, they were strikingly similar in many ways. Both showed similar innate potentials, both had mothers who loved them and wanted them to live in the speaking world, and both were recipients of some of the most powerful technology science had to offer. But that's where the similarities ended. Same potential, same surgery, but very different outcomes.
I could never have learned what I learned from Zach and Michelle in any medical textbook. It is not just that my experience with them made me become aware of the limits of technology; it also made me acknowledge a force whose potential impact I may have always known but had failed to recognize, a force that irrevocably impacts the arcs of all of our lives.
Zach was about eight months old when his parents brought him to see our team, a peanut with hair so light you barely realized he had any. He smiled easily; his blue eyes, the color of a clear sky, watched our every move. His deafness had been a shock to his parents. No one in his family had hearing loss except one cousin who had gotten hearing aids in his sixties. His sister, Emma, two years older than Zach, had normal hearing and was the definition of the chatty older sister. But although his parents had had no contact with anyone who was deaf, they knew what they wanted before they entered my office.
Zach's parents had educated themselves. No-nonsense, quietly determined, they were aware that there were communication choices and they effectively let us know their goal: to have Zach be part of the hearing and speaking world. Zach had already been wearing hearing aids almost since his diagnosis and, astonishingly, while parents often battle children to keep them on, Zach wore his easily, his tiny ears flipped over like palm trees in a hurricane by their weight.
Zach's parents were proactive in other ways, as well. From the beginning they had a therapist come to their home to work with them and Zach on techniques to enhance his language development. They even started to learn sign language because they wanted to make sure Zach would be able to communicate no matter the mode. As a result, sign language was already the connection between Zach and his family.
From the beginning, Zach's parents knew that cochlear implantation was a possibility. The problem for Zach was the timing. His auditory brainstem response (ABR) test, done when he was an infant to determine hearing, had come back “no response,” a flat line streaming across his ABR tracing with no pretty neural peaks indicating a brain's response to sound. The requisite hearing aid trial had also failed; Zach had the most profound form of deafness that exists. How were hearing aids going to make a dent when ninety decibels, the sound of a motorcycle racing by, didn't register a blip in Zach's brain even with hearing aids? Nonetheless, Zach's parents, who never gave up, had Zach fitted with hearing aids in the hope that he was the rare exception and they would actually work. What else were they to do for a year while they waited to comply with FDA guidelines that approved implantation only for children twelve months or older?
Always proactive, Zach's mother, recognizing from the outset that the hearing aids weren't working, sought the answer on her own. When he was a baby, she would lay Zach on her chest and place his tiny hands on her voice box, hoping he would connect the vibrations of her sweet lullabies to sound. In the same spirit of finding a solution, when she brought Zach to see me there was no question of their intent to have cochlear implantation. His first birthday, his parents decided, would be his “hearing” birthday.
While implantation is the first step, the true “hearing birthday” is actually at the moment the cochlear device is activated. A very dramatic moment, it is invariably followed by, “Honey, Honey, do you hear Mommy? Mommy loves you so much,” then, when it's successful, the startled expression of the child followed by a smile, laughter, or even crying. It is an extraordinarily moving experience. See for yourself. Simply search YouTube for “cochlear implant activations” and wait for the tears.
On Zach's real “hearing birthday,” both he and his parents were cool and relaxed. So relaxed, in fact, that they didn't even video record the occasion, one of the few regrets his mother has.
Like all first birthdays, of course, cochlear implant activation day is only the beginning step toward the goal of speech. And while parents often believe, even though they've been counseled to the contrary, that the ride from activation to spoken language is smooth sailing, a few days at the most, it isn't. Just like hearing newborns, newly implanted children must spend about a year soaking in, and learning to understand, the sounds in their world. Not always that easy. Zach, before implantation, could not hear a motorcycle roaring by; after implantation, he could hear the quietest whisper. Nonetheless, while he heard the sounds, his brain didn't have a clue what they represented. Which is what he, and all implanted children, have to learn before they can begin to speak.
Zach's world at home was filled with talking, reading, and singing. But while his parents swore that he was progressing beautifully, this was never apparent to me. During clinic appointments, even bribery with toys, stickers, anything that might prompt a word, failed. So it was only by humorous accident, when he was three years old, that I discovered that, yes, Zach really could talk.
A violin recital, The Gift of Sound, was being performed by members of the Chicago Symphony Orchestra in honor of our implant program, with many of our program's families in attendance. While music swept through our hospital lobby, people milled around, helping themselves from a long table piled high with cookies and other treats. And it was from this table that I received absolute confirmation that Zach could speak. Because, suddenly, somewhere between the brownies and the cookies, in the middle of Paganini or perhaps Beethoven, came high-pitched child's laughter and a loud, gleeful exclamation: “Ewww! Daddy faaaarted.” And it was then that I knew all was going to be fine for Zach.
Zach is now a mainstreamed third grader in public school. The only outside educational services he receives are from a hearing specialist who ensures that his cochlear implant device is in good working order. He learns at grade level, including reading and math, plays with his friends, fights with his older sister, and gets no special treatment from his no-nonsense, loving parents. He is just a nine-year-old boy with intelligence, spirit, and every indication that he will fulfill his potential. His future is not defined by his hearing loss. He is lucky in many ways.
If Zach had been born twenty years earlier, in 1985 rather than 2005, his hearing loss would have defined his future. While there are many ways to live a happy and fulfilled life, even without hearing, the advent of cochlear implantation transformed Zach's education and career choices. This is largely because the ability to hear has an impact on the ability to read and, in consequence, to learn. The domino effect, over a lifetime, is evident. In studies done on adults born deaf and educated solely with sign language, the average literacy level in the past was fourth grade; one-third of deaf adults are functionally illiterate.
These statistics are not, of course, representative of those fortunate to live in homes rich with the language of native or skilled signers. Neither do they discount those in the deaf community who have achieved beautifully in the arts, in the sciences, in life. When there is lack of achievement, however, it is often related to the fact that about 90 percent of deaf children are born to parents who, while loving, cannot communicate with sign language, so that during the child's critical early years, when optimum neuroplasticity permits brain development, the necessary language environment is inadequate.
Compare this to Zach. Born deaf, yet reading at grade level in the third grade, which is often considered the predictor of long-term academic success, Zach is evidence of the perfect alignment of the stars of parental initiative, technology, and medical policy.
A rich language environment “is like oxygen. It's easy to take for granted until you see someone who isn't getting enough.”
—
With apologies to
Nim Tottenham for liberties with her wonderful quote
Seeing the puzzle pieces fit together perfectly allows one to see the beauty of possibility. It also puts into stark relief what happens when a puzzle piece is missing. It's here that Michelle's story and my turning point begin.
Michelle at seven months looked like a Japanese anime heroine; her crystal-blue-eyed gaze was soulful, intelligent, and entrancing; her laughter, joyful. Like Zach, Michelle had been born without hearing but with all the potential in the world. The puzzle piece she was missing was subtle and at first I didn't really know it existed. In fact, if Michelle had come before Zach, I would likely have either accepted her lag in progress as technology's limitations or simply attributed it to the fact that some “just don't benefit.” But Zach had already set the bar, and what was happening to Michelle after her cochlear implant did not come close to my expectations of what should be happening.
Michelle's father had a moderate hearing loss that was correctable with hearing aids and attributable to Waardenburg syndrome, a genetic condition that affects, among other things, hearing. Like Michelle, who also had Waardenburg syndrome, he had widely spaced blue eyes and normal intelligence. Our team counseled Michelle's mother, Laura, at length. It was clear that as much as she loved her daughter, the weight of her world, including being unemployed with little money, and that now included a child with disabilities, was a heavy burden. It was decided that we would first attempt hearing aids, although I felt, with Michelle's hearing loss, they would probably not be enough. If they were not successful, we all agreed that cochlear implantation would be the next option. Soon after Michelle received the hearing aids, however, Laura moved away, and our professional role with Michelle ceased. When they returned a year later, Laura confirmed that the hearing aids were not working and that she had decided to follow our original suggestion to have cochlear implantation.
I clearly remember Michelle's “hearing birthday” at about two years of age. At that time, we celebrated activation by giving the patient a cupcake and a brightly colored balloon. It was, after all, a festive occasion; although, in Michelle's case, a moderate one. When the cochlear implant was activated, Michelle simply continued eating her cupcake, showing very little response. But “very little response,” is quite different from “no response.” Both Michelle's mother and I were delighted; Michelle, it seemed, could hear, which meant she could learn to talk.
Michelle's hearing, with the implants, was eventually evaluated as in the normal range. The audiologist and speech therapist both referred to her as a “sponge,” easily responding to whatever they were trying to elicit from her. But something else was also apparent. While she responded to sound in the testing booth, she neither used nor seemed to understand speech. Her mother had noticed this at home, as well. Ultimately it was acknowledged that while Michelle could hear sounds, she did not understand their meanings, nor did she seem to be able to learn to understand their meanings.
This was very concerning to all of us who worked with Michelle professionally, including her therapists and the audiologist. During our implant team meetings, ways to support Michelle and her mother were discussed, including efforts to accelerate Michelle's language development by exposing her to more sign and spoken language. But none of these interventions was successful. Unlike Zach, who simply became silent in front of me, Michelle was truly silent, her problem far more serious and complex.
What had gone wrong? I had provided the gift of hearing to two deaf children. Why hadn't that been the complete answer to speaking and learning and integrating into the world? What were the salient differences that separated the outcomes of Zach and Michelle? The answer took me out of the world of the deaf into the wide world of all of us. Because the factors that differentiate Zach's and Michelle's abilities to learn are essentially the same that determine reaching learning potentials for all of us.
The reading level in third grade generally predicts the ultimate learning trajectory for all children. In the third grade, Zach is learning and functioning at grade level.
Michelle is also in the third grade, although in a Total Communication classroom. Even with a working cochlear implant she functions with minimal spoken language and only a basic grasp of sign language; the hope for true spoken language a distant dream. In addition, her third-grade reading is barely at the level of a kindergartener, a predictor of her life to come.
Why had the miraculous promise of a cochlear implant passed by this bright little girl with so much potential?
It turns out that what had gone wrong goes wrong more often than I had realized. This fact became starkly apparent when my team and I toured Chicago schools' hearing loss classrooms so that we could better understand the educational landscape our patients entered. The classrooms we visited were divided into “Oral,” where spoken language was the primary form of communication, and “Total Communication,” where, despite its name, sign language was the primary form of communication, with some spoken language. I, of course, had been sure that all of the children I had implanted early would be in the exclusively Oral classrooms. I was very wrong.
The Total Communication classroom had nine students in a semicircle of desks facing the teacher, who was signing to them. The silence was overwhelming.
And then I saw Michelle, whose blue eyes absolutely identified her. I went over and gave her a hug. Michelle, having no idea who I was, looked up at me with a confused, shy smile. No longer the vibrant little toddler I had first known, her sparkle seemed to have faded completely. With reason. Her teacher shared with me the hardships Michelle had gone through, including coming to school with no lunch, wearing dirty clothes and, most important, an inability to communicate well in either spoken or sign language. When I looked at her lovely face, it was hard to say whether I was seeing the tragedy of deafness or the tragedy of poverty. Without question, however, I knew that I was seeing the tragedy of wasted potential.
Two babies had come to me with very similar potentials but with very different outcomes. Yes, their backgrounds were entirely different, but socioeconomic status had never stopped a child from learning to talk. As a surgeon who had put so much faith in this magical puzzle piece that “fit just so,” who had extoled a golden age for children born deaf, I was devastated, humbled, and, above all, newly determined.
Taking the Hippocratic oath meant that my obligation didn't end when I finished operating; it ended when my patient was well. I knew, absolutely, that it was time for me to step outside the comfortable world of the operating room.
At the University of Chicago, I am surrounded by incredible medical and social scientists, including Nobel laureates, many in search of solutions to our world's most vexing problems. It's important to acknowledge that I had never been one of them. My world was the operating room. My ultimate goal was the implanting of cochlear devices to bring hearing to deaf children, making sure they were working properly, giving a hug and a kiss, and assuming all would be well.
So much for assumptions.
The life we are born into is simply the luck of the draw. No infant emerging into this world knows what's in store; there are no checklists for what you can expect in life, no menu that says one from column A, two from column B. And yet, from day one those factors, over which we have no control, have an indelible effect on our entire lives. In addition, while there is no socioeconomic relationship to being loved as a child, or in having parents who want you to be happy and fulfilled, or to having enormous potentials, there are definitely socioeconomic factors that relate to educational attainment, health status, and disease outcome.
This I learned from stepping out of the operating room and into the wide world of social sciences.
The terms “health disparities” and “social determinants of health” relate to the fact that in virtually every disease, from cancer and diabetes to obscure problems such as presbyosmia, the age-related loss of smell, significantly worse outcomes occur in those born into poverty. What I began to understand from my wonderful and esteemed colleagues at the University of Chicago was that Michelle's problems were related to the world into which she had been born. But knowing this provoked other questions. Were we saying that there was no solution? Do we say that's that and go on to another, more promising patient? Anyone who has read Emma Lazarus's poem on the Statue of Liberty, “Give me your tired, your poor . . . the wretched refuse of your teeming shore,” knows that the next step is not accepting the historical “inevitable.” The next step is changing the “inevitable” by finding a solution.
For a surgeon, trying to find a solution to a social problem means having to leave the familiar confines of the hospital and the operating room, a bit like planning a trip to the moon. On my way to work, I had often crossed the beautifully landscaped historic stretch of Gothic carved stone architecture known as the “Quad,” where University of Chicago research scientists, otherwise known as the “Giants,” do their thinking, teaching, and studying. And it was in that community of social scientists committed to finding out the intricacies of human behavior that I would begin to understand why Michelle's language had never developed as it should have and, most important, how I might have helped.
Professor Susan Levine and Professor Susan Goldin-Meadow, otherwise known as “the Susans,” are University of Chicago professors of psychology, colleagues, longtime friends, and next-door neighbors. For four decades they have been working together to understand how children learn language. They opened my eyes, or rather, provided me with a new lens with which to see the world, especially the world of language acquisition.
I audited Susan Goldin-Meadow's undergraduate class Introduction to Child Language Development during a bitter Chicago winter. Often running late from my clinic, I would rush through the Quad, a heavy down coat covering my white lab coat, which, in turn, was covering my green scrubs. In the antiquated auditorium a steep incline of desk chairs funneled down to the lecture podium. As if proximity would compensate for the neurons no longer firing as rapidly as those of the college students surrounding me, I usually sat in the front row, listening as the students enthusiastically debated the Chomsky-versus-Skinner opposing theories of language acquisition. Was Chomsky correct that each of us is born with a “language acquisition device,” an internal hard drive with the grammatical rules of language already preloaded into our brains? Was learning language our innate biological destiny? Or was Skinner correct when he hypothesized that learning language was not innate, but simply a phenomenon of adult reinforcement, eventually guiding children to acceptable language patterns? These were questions far from the cut-and-sew setting of the operating room, but they were now absolutely part of my world. I was acutely alert, waiting for the insights I needed to help the children I cared for.